これは単純なクライアント サーバー チャット プログラムです。このコードは、ネットワークに接続されたコンピューターで正常に動作します。インターネットを介してコンピューター間で接続できるように変更する方法を教えてください。サーバーのパブリック IP を使用しても機能しgethostbyname()ません。
//Client.c
#include<stdio.h>
#include<sys/types.h>
#include<sys/socket.h>
#include<netinet/in.h>
#include<netdb.h>
#include<unistd.h>
#include<string.h>
#include<stdlib.h>
int main(void)
{
int clientSocket; /* Socket Decriptor for Client */
struct sockaddr_in server_addr;
struct hostent *ptrh;
char message[100];
char received[100];
int n = 0;
clientSocket=socket(AF_INET, SOCK_STREAM, 0);
memset((char*)&server_addr, 0, sizeof(server_addr));
server_addr.sin_family = AF_INET;
server_addr.sin_port = htons(10000);
/* bind(clientSocket, (struct sockaddr*)&server_addr, sizeof(struct sockaddr)); */
ptrh=gethostbyname("110.172.156.2");
memcpy(&server_addr.sin_addr,ptrh->h_addr,ptrh->h_length);
if( -1 == (connect(clientSocket, (struct sockaddr*)&server_addr, sizeof(server_addr))))
{ printf("\nServer Not Ready !!\n"); exit(1); }
while(1)
{
printf("\nUser:-");
// memset(message, '\0', 10);
gets(message);
n = write(clientSocket, message, strlen(message)+1);
if( (strcmp(message,"q") == 0 ) || (strcmp(message,"Q") == 0 ))
{
printf("Wrong place...Socket Closed\n");
close(clientSocket);
break;
}
//printf("Write:<%u>\n", n);
read(clientSocket, received, sizeof(received));
if( (strcmp(received,"q") == 0 ) || (strcmp(received,"Q") == 0 ))
{
printf("Wrong place...Socket Closed\n");
close(clientSocket);
break;
}
else
printf("Server:- %s\n", received);
}
return 0;
}
//Server.c
#include<sys/types.h>
#include<sys/socket.h>
#include<netinet/in.h>
#include<stdio.h>
#include<stdlib.h>
#include<unistd.h>
#include<string.h>
#include<netdb.h>
int main(void)
{
int serverSocket,client_connected,len;
struct sockaddr_in client_addr,server_addr;
struct hostent *ptrh;
int n=0;
char message[100],received[100];
serverSocket=socket(AF_INET, SOCK_STREAM, 0);
memset((char*)&server_addr,0,sizeof(server_addr));
server_addr.sin_family = AF_INET;
server_addr.sin_port = htons(10000);
server_addr.sin_addr.s_addr = htonl(INADDR_ANY);
if(bind(serverSocket,
(struct sockaddr*)&server_addr,sizeof(server_addr)) == -1)
printf("Bind Failure\n");
else
printf("Bind Success:<%u>\n", serverSocket);
while(1)
{
listen(serverSocket,5);
len=sizeof(struct sockaddr_in);
client_connected=accept(serverSocket,
(struct sockaddr*)&client_addr,&len);
if (-1 != client_connected)
printf("Connection accepted:<%u>\n", client_connected);
while(1)
{
n = read(client_connected, received, sizeof(received));
if( (strcmp(received,"q") == 0 ) || (strcmp(received,"Q") == 0 ))
{
printf("Wrong place...Socket Closed of Client\n");
close(client_connected);
break;
}
else{
printf("\nUser:-%s", received);}
printf("\nServer:-");
// memset(message, '\0', 10);
gets(message);
write(client_connected, message, sizeof(message));
if( (strcmp(message,"q") == 0 ) || (strcmp(message,"Q") == 0 ))
{
printf("Wrong place...Socket Closed of Client\n");
close(client_connected);
break;
}
}
}
close(serverSocket); printf("\nServer Socket Closed !!\n");
return 0;
}